uvm_fault(0xfffffd807ec932b0, 0x8, 0, 1) -> e kernel: page fault trap, code=0 Stopped at fifo_write+0x6e: movq 0x8(%rax),%r15 TID PID UID PRFLAGS PFLAGS CPU COMMAND *392476 22596 0 0x2 0x1 0 syz-executor fifo_write(ffff80002a4c2cc0) at fifo_write+0x6e sys/miscfs/fifofs/fifo_vnops.c:281 VOP_WRITE(fffffd8070de7dc0,ffff80002a4c2d70,3,fffffd807f7d7340) at VOP_WRITE+0x102 sys/kern/vfs_vops.c:245 ktrwriteraw(ffff80002a456290,fffffd8070de7dc0,fffffd807f7d7340,ffff80002a4c2e38,ffff80002a4c2e10) at ktrwriteraw+0x191 sys/kern/kern_ktrace.c:682 ktrgenio(ffff80002a456290,3,0,ffff800001292e10,4) at ktrgenio+0x2b6 ktrwrite2 sys/kern/kern_ktrace.c:644 [inline] ktrgenio(ffff80002a456290,3,0,ffff800001292e10,4) at ktrgenio+0x2b6 sys/kern/kern_ktrace.c:258 dofilereadv(ffff80002a456290,3,ffff80002a4c2fa8,0,ffff80002a4c3060) at dofilereadv+0x42c sys/kern/sys_generic.c:268 sys_read(ffff80002a456290,ffff80002a4c3110,ffff80002a4c3060) at sys_read+0xa2 sys/kern/sys_generic.c:172 syscall(ffff80002a4c3110) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x76ac11debfa0, count: 7 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: uvm_fault(0xfffffd807ec932b0, 0x8, 0, 1) -> e ddb> trace fifo_write(ffff80002a4c2cc0) at fifo_write+0x6e sys/miscfs/fifofs/fifo_vnops.c:281 VOP_WRITE(fffffd8070de7dc0,ffff80002a4c2d70,3,fffffd807f7d7340) at VOP_WRITE+0x102 sys/kern/vfs_vops.c:245 ktrwriteraw(ffff80002a456290,fffffd8070de7dc0,fffffd807f7d7340,ffff80002a4c2e38,ffff80002a4c2e10) at ktrwriteraw+0x191 sys/kern/kern_ktrace.c:682 ktrgenio(ffff80002a456290,3,0,ffff800001292e10,4) at ktrgenio+0x2b6 ktrwrite2 sys/kern/kern_ktrace.c:644 [inline] ktrgenio(ffff80002a456290,3,0,ffff800001292e10,4) at ktrgenio+0x2b6 sys/kern/kern_ktrace.c:258 dofilereadv(ffff80002a456290,3,ffff80002a4c2fa8,0,ffff80002a4c3060) at dofilereadv+0x42c sys/kern/sys_generic.c:268 sys_read(ffff80002a456290,ffff80002a4c3110,ffff80002a4c3060) at sys_read+0xa2 sys/kern/sys_generic.c:172 syscall(ffff80002a4c3110) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x76ac11debfa0, count: -8 ddb> show registers rdi 0xfffffd8070de7dc0 rsi 0x1 rbp 0xffff80002a4c2cb0 rbx 0x4c rdx 0 rcx 0x1 rax 0 r8 0xffff80002a4c2e10 r9 0xffff80002a4c2ec4 r10 0xfe54f05e50bac0b1 r11 0xff36e9fc47d5a11b r12 0x4000 __ALIGN_SIZE+0x3000 r13 0xffff80002a4c2d70 r14 0xffff80002a4c2cc0 r15 0x1 rip 0xffffffff81ef275e fifo_write+0x6e cs 0x8 rflags 0x10246 __ALIGN_SIZE+0xf246 rsp 0xffff80002a4c2c80 ss 0x10 fifo_write+0x6e: movq 0x8(%rax),%r15 ddb> show proc PROC (syz-executor) tid=392476 pid=22596 tcnt=1 stat=onproc flags process=2 proc=1 runpri=84, usrpri=84, slppri=24, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a456518,0xffff800037618540 process=0xffff8000ffff8010 user=0xffff80002a4be000, vmspace=0xfffffd807ec932b0 estcpu=34, cpticks=1, pctcpu=0.0, user=5, sys=8, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 27376 173078 5956 0 3 0x80 nanoslp syz-executor 27376 243150 5956 0 2 0x4000000 syz-executor 27376 12726 5956 0 3 0x4000080 fsleep syz-executor 56212 408485 3414 0 2 0x40 syz-executor 54012 466488 83709 0 2 0 syz-executor 54012 243693 83709 0 3 0x4000080 fsleep syz-executor 54012 221727 83709 0 3 0x4000080 fsleep syz-executor 90518 179203 81320 0 2 0x100002 sh 57082 244546 74903 0 2 0 syz-executor 57082 292073 74903 0 3 0x4000080 netcon syz-executor 57082 302297 74903 0 3 0x4000080 fsleep syz-executor 81320 160681 22596 0 3 0x82 wait syz-executor 3414 441330 22596 0 3 0x82 ppwait syz-executor 73247 253685 22596 0 3 0x82 piperd syz-executor 15539 30004 22596 0 2 0x2 syz-executor 74903 376651 22596 0 2 0x482 syz-executor 7457 289152 22596 0 3 0x82 piperd syz-executor 5956 360763 22596 0 3 0x82 nanoslp syz-executor 83709 369893 22596 0 2 0x482 syz-executor 27648 14876 1 0 3 0x100083 ttyin getty 2733 428267 0 0 3 0x14200 bored sosplice *22596 392476 67669 0 7 0x3 syz-executor 67669 276035 31523 0 3 0x10008a sigsusp ksh 31523 291441 975 0 3 0x98 kqread sshd-session 975 395752 41104 0 3 0x92 kqread sshd-session 41104 49009 1 0 3 0x88 kqread sshd 92208 258559 48885 73 2 0x1100010 syslogd 48885 152324 1 0 3 0x100082 sbwait syslogd 67969 16107 1 0 3 0x100080 kqread resolvd 81340 329873 79080 77 3 0x100092 kqread dhcpleased 98536 121137 79080 77 3 0x100092 kqread dhcpleased 79080 250292 1 0 3 0x80 kqread dhcpleased 13932 369926 0 0 3 0x14200 bored smr 60056 194600 0 0 2 0x14200 zerothread 65906 301999 0 0 3 0x14200 aiodoned aiodoned 324 514429 0 0 3 0x14200 syncer update 65077 361505 0 0 3 0x14200 cleaner cleaner 57246 403576 0 0 3 0x14200 reaper reaper 90050 288344 0 0 3 0x14200 pgdaemon pagedaemon 52274 301802 0 0 3 0x14200 bored viomb 40574 24363 0 0 3 0x40014200 acpi0 acpi0 42107 188141 0 0 3 0x14200 bored softnet3 43498 245796 0 0 3 0x14200 bored softnet2 95625 330451 0 0 3 0x14200 bored softnet1 52457 503309 0 0 3 0x14200 bored softnet0 62427 408859 0 0 3 0x14200 bored systqmp 22252 443556 0 0 3 0x14200 bored systq 68707 386528 0 0 3 0x40014200 tmoslp softclock 71421 319991 0 0 3 0x40014200 idle0 1 444190 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10210 10105K 10355K 166960K 12126 0 pcb 17 16K 18K 166960K 210 0 rtable 218 8K 9K 166960K 1981 0 pf 35 14K 22K 166960K 197 0 ifaddr 41 8K 8K 166960K 316 0 ifgroup 50 2K 2K 166960K 270 0 sysctl 1 0K 0K 166960K 1 0 counters 30 17K 17K 166960K 88 0 ioctlops 0 0K 4K 166960K 127 0 iov 0 0K 16K 166960K 70 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1392 88K 88K 166960K 2434 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 16 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 21 0 dirhash 12 2K 2K 166960K 27 0 ACPI 1697 195K 286K 166960K 12548 0 file desc 15 53K 97K 166960K 1390 0 sigio 0 0K 0K 166960K 40 0 proc 58 59K 124K 166960K 1874 0 subproc 104 6K 6K 166960K 728 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 163 0 in_multi 89 6K 7K 166960K 634 0 ether_multi 1 0K 0K 166960K 6 0 mrt 1 0K 0K 166960K 3 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 229 1023K 1023K 166960K 229 0 exec 0 0K 2K 166960K 1097 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 191 71K 91K 166960K 11318 0 UVM aobj 87 3K 3K 166960K 87 0 pinsyscall 36 72K 106K 166960K 3644 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 30 0 NDP 13 0K 2K 166960K 179 0 temp 70 6814K 6937K 166960K 52173 0 kqueue 13 20K 30K 166960K 122 0 SYN cache 2 16K 16K 166960K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 212 0 207 2 0 2 2 0 8 1 rtentry 112 709 0 612 4 0 4 4 0 8 1 unpcb 144 894 0 877 6 0 6 6 0 8 5 syncache 336 3 0 3 1 0 1 1 0 8 1 tcpcb 808 349 0 344 8 0 8 8 0 8 7 arp 88 116 0 99 1 0 1 1 0 8 0 ipq 40 8 0 6 1 0 1 1 0 8 0 ipqe 40 17 0 14 1 0 1 1 0 8 0 inpcb 336 1319 0 1311 10 1 9 10 0 8 8 nd6 104 168 0 148 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 0 1 1 0 8 1 kcovpl 48 56 0 48 1 0 1 1 0 8 0 ppxss 1072 7 0 7 1 0 1 1 0 8 1 pfosfp 40 1 0 0 1 0 1 1 0 8 0 pfosfpen 112 1 0 0 1 0 1 1 0 8 0 pfrktable 1344 14 0 11 1 0 1 1 0 8 0 pfanchor 1288 1 0 0 1 0 1 1 0 8 0 pfqueue 264 1 0 1 1 0 1 1 0 8 1 pfstitem 24 2 0 0 1 0 1 1 0 8 0 pfstkey 128 4 0 2 1 0 1 1 0 8 0 pfstate 344 2 0 1 1 0 1 1 0 8 0 pfrule 1344 16 0 5 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 2545 0 2135 29 0 29 29 0 8 3 art_table 32 2546 0 2135 4 0 4 4 0 8 0 art_node 16 642 0 555 1 0 1 1 0 8 0 sysvmsgpl 40 14 0 2 1 0 1 1 0 8 0 semapl 112 18 0 8 1 0 1 1 0 8 0 shmpl 112 84 0 0 3 0 3 3 0 8 0 dirhash 1024 27 0 10 3 0 3 3 0 8 0 dino2pl 256 2658 0 1077 99 0 99 99 0 8 0 ffsino 240 2658 0 1077 94 0 94 94 0 8 0 nchpl 144 3635 0 1893 65 0 65 65 0 8 0 uvmvnodes 80 3669 0 0 75 0 75 75 0 8 0 vnodes 216 3669 0 0 204 0 204 204 0 8 0 namei 1024 17041 0 17040 2 0 2 2 0 8 1 pfiaddrpl 120 12 0 1 1 0 1 1 0 8 0 kstatmem 264 138 0 116 2 0 2 2 0 8 0 scxspl 216 29378 0 29378 8 0 8 8 1 8 8 plimitpl 152 393 0 377 1 0 1 1 0 8 0 sigapl 424 1577 0 1533 7 0 7 7 0 8 1 futexpl 64 9451 0 9447 1 0 1 1 0 8 0 knotepl 120 22002 0 21955 17 7 10 17 0 8 8 kqueuepl 184 178 0 169 1 0 1 1 0 8 0 pipepl 288 286 0 258 3 0 3 3 0 8 0 fdescpl 432 1559 0 1532 5 0 5 5 0 8 1 filepl 120 7710 0 7461 15 0 15 15 0 8 7 lockfpl 104 240 0 237 1 0 1 1 0 8 0 lockfspl 48 95 0 92 1 0 1 1 0 8 0 sessionpl 144 70 0 62 1 0 1 1 0 8 0 pgrppl 48 132 0 116 1 0 1 1 0 8 0 ucredpl 104 799 0 788 1 0 1 1 0 8 0 zombiepl 144 1533 0 1533 1 0 1 1 0 8 1 processpl 1096 1577 0 1533 4 0 4 4 0 8 0 procpl 648 2423 0 2373 6 0 6 6 0 8 1 sosppl 168 2 0 2 1 0 1 1 0 8 1 sockpl 504 2436 0 2406 41 29 12 25 0 8 7 mcl64k 65536 4 0 4 1 0 1 1 0 8 1 mcl16k 16384 1 0 1 1 0 1 1 0 8 1 mcl9k 9216 2 0 2 1 0 1 1 0 8 1 mcl8k 8192 24 0 24 1 0 1 1 0 8 1 mcl4k 4096 6 0 6 1 0 1 1 0 8 1 mcl2k 2048 7297 0 7179 24 3 21 24 0 8 6 mtagpl 96 14 0 14 1 0 1 1 0 8 1 mbufpl 256 16697 0 16398 20 0 20 20 0 8 0 bufpl 280 7560 0 1315 447 0 447 447 0 8 0 anonpl 24 258313 0 255291 74 0 74 74 0 187 46 amapchunkpl 152 36088 0 35709 32 0 32 32 0 158 13 amappl16 200 4806 0 4798 22 13 9 15 0 8 8 amappl15 192 13 0 13 1 0 1 1 0 8 1 amappl14 184 208 0 196 1 0 1 1 0 8 0 amappl13 176 5 0 5 1 0 1 1 0 8 1 amappl12 168 2916 0 2889 3 0 3 3 0 8 1 amappl11 160 49 0 39 1 0 1 1 0 8 0 amappl10 152 11 0 11 1 0 1 1 0 8 1 amappl9 144 134 0 134 1 0 1 1 0 8 1 amappl8 136 21 0 20 1 0 1 1 0 8 0 amappl7 128 191 0 180 1 0 1 1 0 8 0 amappl6 120 635 0 633 1 0 1 1 0 8 0 amappl5 112 324 0 315 1 0 1 1 0 8 0 amappl4 104 448 0 431 1 0 1 1 0 8 0 amappl3 96 6238 0 6161 3 0 3 3 0 8 0 amappl2 88 1882 0 1810 2 0 2 2 0 8 0 amappl1 80 14134 0 13610 15 0 15 15 0 8 3 amappl 88 10601 0 10464 5 0 5 5 0 92 1 dma65536 65536 1 0 1 1 0 1 1 0 8 1 dma4096 4096 1 0 1 1 0 1 1 0 8 1 dma1024 1024 3 0 2 1 0 1 1 0 8 0 dma256 256 6 0 6 1 0 1 1 0 8 1 dma128 128 253 0 253 1 0 1 1 0 8 1 dma64 64 8 0 8 1 0 1 1 0 8 1 dma32 32 7 0 7 1 0 1 1 0 8 1 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 86 0 0 2 0 2 2 0 8 0 uaddrrnd 24 1559 0 1532 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1559 0 1532 1 0 1 1 0 8 0 vmmpekpl 168 13211 0 13155 3 0 3 3 0 8 0 vmmpepl 168 101481 0 99893 91 0 91 91 0 357 13 vmsppl 344 1558 0 1532 4 0 4 4 0 8 1 rwobjpl 24 34430 0 29848 29 0 29 29 0 8 0 pdppl 4096 3125 0 3064 169 98 71 83 0 8 10 pvpl 32 909466 0 901039 257 0 257 257 0 265 172 pmappl 216 1558 0 1532 3 0 3 3 0 8 1 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 512 0 131 12 0 12 12 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace fifo_write(ffff80002a4c2cc0) at fifo_write+0x6e sys/miscfs/fifofs/fifo_vnops.c:281 VOP_WRITE(fffffd8070de7dc0,ffff80002a4c2d70,3,fffffd807f7d7340) at VOP_WRITE+0x102 sys/kern/vfs_vops.c:245 ktrwriteraw(ffff80002a456290,fffffd8070de7dc0,fffffd807f7d7340,ffff80002a4c2e38,ffff80002a4c2e10) at ktrwriteraw+0x191 sys/kern/kern_ktrace.c:682 ktrgenio(ffff80002a456290,3,0,ffff800001292e10,4) at ktrgenio+0x2b6 ktrwrite2 sys/kern/kern_ktrace.c:644 [inline] ktrgenio(ffff80002a456290,3,0,ffff800001292e10,4) at ktrgenio+0x2b6 sys/kern/kern_ktrace.c:258 dofilereadv(ffff80002a456290,3,ffff80002a4c2fa8,0,ffff80002a4c3060) at dofilereadv+0x42c sys/kern/sys_generic.c:268 sys_read(ffff80002a456290,ffff80002a4c3110,ffff80002a4c3060) at sys_read+0xa2 sys/kern/sys_generic.c:172 syscall(ffff80002a4c3110) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x76ac11debfa0, count: -8 ddb> machine ddbcpu 1 No such command ddb> trace fifo_write(ffff80002a4c2cc0) at fifo_write+0x6e sys/miscfs/fifofs/fifo_vnops.c:281 VOP_WRITE(fffffd8070de7dc0,ffff80002a4c2d70,3,fffffd807f7d7340) at VOP_WRITE+0x102 sys/kern/vfs_vops.c:245 ktrwriteraw(ffff80002a456290,fffffd8070de7dc0,fffffd807f7d7340,ffff80002a4c2e38,ffff80002a4c2e10) at ktrwriteraw+0x191 sys/kern/kern_ktrace.c:682 ktrgenio(ffff80002a456290,3,0,ffff800001292e10,4) at ktrgenio+0x2b6 ktrwrite2 sys/kern/kern_ktrace.c:644 [inline] ktrgenio(ffff80002a456290,3,0,ffff800001292e10,4) at ktrgenio+0x2b6 sys/kern/kern_ktrace.c:258 dofilereadv(ffff80002a456290,3,ffff80002a4c2fa8,0,ffff80002a4c3060) at dofilereadv+0x42c sys/kern/sys_generic.c:268 sys_read(ffff80002a456290,ffff80002a4c3110,ffff80002a4c3060) at sys_read+0xa2 sys/kern/sys_generic.c:172 syscall(ffff80002a4c3110) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x76ac11debfa0, count: -8